Parana River Basin Freshwater for January 1985 - 1999

Runoff in the Parana basin follows a seasonal cycle linked to rainfall. Highest runoff estimates are for the period January to April and lowest from May to September. This pattern follows the rainfall trend when the period May to Sept experiences lower rain fall than the rest of the year. The varied year to year differences in December show higher runoff estimates for 1987, 1992, 1997 which were years with strong El Nino events.